Buggy code:
public class TestBeanGUI extends AbstractJMeterGuiComponent { private static Logger log = LoggingManager . getLoggerForClass ( ) ; public static final String GROUP = "group" ; public static final String ORDER = "order" ; public static final String TAGS = "tags" ; public static final String NOT_UNDEFINED = "notUndefined" ; public static final String NOT_EXPRESSION = "notExpression" ; public static final String NOT_OTHER = "notOther" ; public static final String DEFAULT = "default" ; public static final String RESOURCE_BUNDLE = "resourceBundle" ; public static final String ORDER ( String group ) { } public static final String DEFAULT_GROUP = "" ; private Class testBeanClass ; private BeanInfo beanInfo ; private PropertyDescriptor [ ] descriptors ; private PropertyEditor [ ] editors ; private MessageFormat propertyFieldLabelMessage ; private MessageFormat propertyToolTipMessage ; public TestBeanGUI ( Class testBeanClass ) { } private WrapperEditor createWrapperEditor ( PropertyEditor typeEditor , PropertyDescriptor descriptor ) { String [ ] editorTags = typeEditor . getTags ( ) ; String [ ] additionalTags = ( ( String [ ] ) ( descriptor . getValue ( TestBeanGUI . TAGS ) ) ) ; String [ ] tags = null ; if ( editorTags == null ) tags = additionalTags ; else if ( additionalTags == null ) tags = editorTags ; else { tags = new String [ ( editorTags . length ) + ( additionalTags . length ) ] ; int j = 0 ; for ( int i = 0 ; i < ( editorTags . length ) ; i ++ ) tags [ ( j ++ ) ] = editorTags [ i ] ; for ( int i = 0 ; i < ( additionalTags . length ) ; i ++ ) tags [ ( j ++ ) ] = additionalTags [ i ] ; } boolean notNull = Boolean . TRUE . equals ( descriptor . getValue ( TestBeanGUI . NOT_UNDEFINED ) ) ; boolean notExpression = Boolean . TRUE . equals ( descriptor . getValue ( TestBeanGUI . NOT_EXPRESSION ) ) ; boolean notOther = Boolean . TRUE . equals ( descriptor . getValue ( TestBeanGUI . NOT_OTHER ) ) ; PropertyEditor guiEditor ; if ( notNull && ( tags == null ) ) { guiEditor = new FieldStringEditor ( ) ; } else { ComboStringEditor e = new ComboStringEditor ( ) ; e . setNoUndefined ( notNull ) ; e . setNoEdit ( ( notExpression && notOther ) ) ; e . setTags ( tags ) ; guiEditor = e ; } WrapperEditor wrapper = new WrapperEditor ( typeEditor , guiEditor , ( ! notNull ) , ( ! notExpression ) , ( ! notOther ) ) ; Object defaultValue = descriptor . getValue ( TestBeanGUI . DEFAULT ) ; try { wrapper . setValue ( defaultValue ) ; } catch ( IllegalArgumentException e ) { TestBeanGUI . log . error ( ( ( ( "The<seq2seq4repair_space>default<seq2seq4repair_space>value<seq2seq4repair_space>for<seq2seq4repair_space>property<seq2seq4repair_space>" + ( descriptor . getName ( ) ) ) + "<seq2seq4repair_space>is<seq2seq4repair_space>not<seq2seq4repair_space>valid.<seq2seq4repair_space>Or<seq2seq4repair_space>a<seq2seq4repair_space>default<seq2seq4repair_space>value<seq2seq4repair_space>was<seq2seq4repair_space>not<seq2seq4repair_space>provided<seq2seq4repair_space>and<seq2seq4repair_space>" ) + "<seq2seq4repair_space>property<seq2seq4repair_space>attribute<seq2seq4repair_space>notUndefined<seq2seq4repair_space>is<seq2seq4repair_space>set<seq2seq4repair_space>to<seq2seq4repair_space>true." ) ) ; throw new Error ( e . toString ( ) ) ; } if ( guiEditor instanceof ComboStringEditor ) { String v ; if ( notOther ) v = "${}" ; else if ( notNull ) v = "" ; else if ( defaultValue != null ) v = wrapper . getAsText ( ) ; else <START_BUG> if ( tags != null ) <END_BUG> v = tags [ 1 ] ; else if ( notExpression ) v = "" ; else v = "${}" ; ( ( ComboStringEditor ) ( guiEditor ) ) . setInitialEditValue ( v ) ; } return wrapper ; } private void setEditorValue ( int i , Object value ) throws IllegalArgumentException { } public String getStaticLabel ( ) { } public void configure ( TestElement element ) { } private int descriptorIndex ( String name ) { } public TestElement createTestElement ( ) { } public void modifyTestElement ( TestElement element ) { } private static JMeterProperty wrapInProperty ( Object value ) { } public JPopupMenu createPopupMenu ( ) { } public Collection getMenuCategories ( ) { } private void init ( ) { } private JLabel createLabel ( PropertyDescriptor desc ) { } private String group ( PropertyDescriptor d ) { } private String groupDisplayName ( String group ) { } private class PropertyComparator implements Comparator { public int compare ( Object o1 , Object o2 ) { } private int compare ( PropertyDescriptor d1 , PropertyDescriptor d2 ) { } private Integer groupOrder ( String group ) { } private Integer propertyOrder ( PropertyDescriptor d ) { } } }

Fix:
if ( ( tags != null ) && ( ( tags . length ) > 0 ) )